1. Field of the Invention
The present invention relates to a semiconductor wafer processing film consisting of a base film, pressure-sensitive adhesive layer, release film and surfactant layer. More particularly, the invention relates to a wafer processing film which can prevent failure caused by static electricity and can also inhibit contamination and corrosion of the water.
2. Description of the Related Art
A semiconductor integrated circuit (IC) is manufactured by slicing a single crystal of silicon to obtain a wafer, followed by installing an integrated circuit through etching and then passing through steps such as dicing, washing, drying, expanding and pick up. A wafer processing film has been used in order to prevent failure of the wafer during these steps and to carry out fabrication with ease. However, static electricity generated by the handling of the wafer processing film in these steps sometimes damages the semiconductor integrated circuit on the wafer by electric discharge.
A method for fitting a destaticizer such as an antistatic bar on the wafer processing film or a method for blowing ionized air to temporarily destaticize the wafer are employed in order to prevent these problems. These methods, however, are not very effective and have a disadvantage of making the steps complex.
In order to improve these drawbacks, Japanese Laid-Open Patent 80834 (1986) has proposed a method for adding electrically conductive substances such as metal powder to either or both of a substrate material and pressure-sensitive adhesive itself, thereby making the adhesive film conductive and thereby preventing generation of static electricity. The method, however, leads to contamination of the wafer surface by the electrically conductive substances contained in the pressure-sensitive adhesive and causes such adverse effects as corrosion of the wafer.
Japanese Laid-Open Patent 191777 (1983) has disclosed a method for preventing electrification by addition of surfactant to adhesive. The method, however, brings surfactant contained in the adhesive into direct contact with the surface of the wafer and thereby contaminating the wafer.